/*
 * Copyright © 2015 Cask Data, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package co.cask.cdap.dq.functions;

import co.cask.cdap.dq.DataQualityWritable;

/**
 * Basic Aggregation Function Interface: All aggregation function classes -- combinable or non-combinable
 * -- should implement these methods
 * @param <T> Type of the aggregation
 */
public interface BasicAggregationFunction<T> {

  /**
   * Incrementally add values to the aggregation
   */
  void add(DataQualityWritable value);

  /**
   * Return the aggregation accumulated using add() in the form of a byte[]
   */
  byte[] aggregate();

  /**
   * Deserialize a given value appropriately
   */
  T deserialize(byte[] value);

}
